Sequelize using postgres dialect add double column

I want to create a relationship between parents table and children table and this is how i doing it

// 20210226075430-create-child.js (children migration file)

module.exports = {
  up: async (queryInterface, Sequelize) => {
    await queryInterface.createTable("Children", {
      id: {
        allowNull: false,
        autoIncrement: true,
        primaryKey: true,
        type: Sequelize.INTEGER,
      },
      name: {
        type: Sequelize.STRING,
      },
      age: {
        type: Sequelize.STRING,
      },
      parentId: {
        type: Sequelize.INTEGER,
        allowNull: false,
        onDelete: "CASCADE",
        references: {
          model: "Parents",
          key: "id",
        },
      },
      createdAt: {
        allowNull: false,
        type: Sequelize.DATE,
      },
      updatedAt: {
        allowNull: false,
        type: Sequelize.DATE,
      },
    });
  },
  down: async (queryInterface, Sequelize) => {
    await queryInterface.dropTable("Children");
  },
};

// parent migration file

module.exports = {
  up: async (queryInterface, Sequelize) => {
    await queryInterface.createTable("Parents", {
      id: {
        allowNull: false,
        autoIncrement: true,
        primaryKey: true,
        type: Sequelize.INTEGER,
      },
      name: {
        type: Sequelize.STRING,
      },
      age: {
        type: Sequelize.STRING,
      },
      createdAt: {
        allowNull: false,
        type: Sequelize.DATE,
      },
      updatedAt: {
        allowNull: false,
        type: Sequelize.DATE,
      },
    });
  },
  down: async (queryInterface, Sequelize) => {
    await queryInterface.dropTable("Parents");
  },
};

// child.js / children model

"use strict";
const { Model } = require("sequelize");
module.exports = (sequelize, DataTypes) => {
  class Child extends Model {
    /**
     * Helper method for defining associations.
     * This method is not a part of Sequelize lifecycle.
     * The `models/index` file will call this method automatically.
     */
    static associate(models) {
      // define association here
      Child.belongsTo(models.Parent, { foreignKey: "parentId" });
    }
  }
  Child.init(
    {
      name: DataTypes.STRING,
      age: DataTypes.STRING,
      parentId: DataTypes.INTEGER,
    },
    {
      sequelize,
      modelName: "Child",
    }
  );
  return Child;
};

// parent model

"use strict";
const { Model } = require("sequelize");
module.exports = (sequelize, DataTypes) => {
  class Parent extends Model {
    /**
     * Helper method for defining associations.
     * This method is not a part of Sequelize lifecycle.
     * The `models/index` file will call this method automatically.
     */
    static associate(models) {
      // define association here
      Parent.hasMany(models.Child);
    }
  }
  Parent.init(
    {
      name: DataTypes.STRING,
      age: DataTypes.STRING,
    },
    {
      sequelize,
      modelName: "Parent",
    }
  );
  return Parent;
};

this code perfectly fine in mysql but when i change dialect to postgres i got error like this :

Executing (default): SELECT "id", "name", "age", "parentId", "createdAt", "updatedAt", "ParentId" FROM "Children" AS "Child";
(node:7496) UnhandledPromiseRejectionWarning: SequelizeDatabaseError: column "ParentId" does not exist
    at Query.formatError (D:workwwwexpress-starternode_modulessequelizelibdialectspostgresquery.js:386:16)
    at Query.run (D:workwwwexpress-starternode_modulessequelizelibdialectspostgresquery.js:87:18)
    at processTicksAndRejections (internal/process/task_queues.js:97:5)
(node:7496) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:7496) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

I have already tried to add foreign key in child.js (model) but i still got this error.

where i doing it wrong?

Answer

You didn’t indicate parentId as a foreignKey option in the association from Parent to Children that’s why Sequelize automatically generates its name like ParentId. Just indicate the same option and value as in belongsTo like this:

Parent.hasMany(models.Child, { foreignKey: "parentId" });

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